KERN MWB series User manual

KERN & Sohn GmbH
Ziegelei 1
D-72336 Balingen
E-Mail: [e-mail]
Tel: +49-[0]7433- 9933-0
Fax: +49-[0]7433-9933-149
Internet: www.kern-sohn.com
Service Manual
Wheelchair scale
KERN MWB
Version 1.0
03/2018
GB
MWB-SH-e-1810
Importør:
Impex Produkter AS
Gamle Drammensvei 107
1363 Høvik
www.impex.no
[email protected]
Tel.: [phone]

2 MWB-SH-e-1810.docx
GB
KERN MWB
Wheelchair scale
Version 1.0 04/2018
Service manual
Content
1Basic Information............................................................................................... 4
2Introdution.......................................................................................................... 4
3Appliance overview............................................................................................ 5
3.1 Details....................................................................................................................................6
3.2 Overview display...................................................................................................................7
3.3 Overview Keyboard...............................................................................................................8
4Basic Information (General).............................................................................. 9
4.1 Proper use .............................................................................................................................9
4.2 Improper Use.........................................................................................................................9
4.3 Warranty ................................................................................................................................9
4.4 Monitoring of Test Resources ..............................................................................................9
5Basic Safety Precautions ................................................................................ 10
5.1 Pay attention to the instructions in the Operation Manual................................................10
6Transport and storage..................................................................................... 10
6.1 Testing upon acceptance....................................................................................................10
6.2 Packaging / return transport...............................................................................................10
7Unpacking, Setup and Commissioning.......................................................... 11
7.1 Place of installation / place of operation............................................................................11
7.2 Unpacking............................................................................................................................11
7.3 Scope of delivery.................................................................................................................11
7.4 Levelling ..............................................................................................................................11
8Menu.................................................................................................................. 12
8.1 Navigation in the menu .......................................................................................................12
8.2 Menu overview.....................................................................................................................12
9Error Messages................................................................................................ 14
10 Servicing, maintenance, disposal ............................................................... 15
10.1 Cleaning...............................................................................................................................15
10.2 Cleaning / disinfecting ........................................................................................................15
10.3 Servicing, maintenance.......................................................................................................15
10.4 Disposal...............................................................................................................................15
11 Instant help.................................................................................................... 15
12 Adjustment.................................................................................................... 17
13 MAINTENENCE ............................................................................................. 18
13.1 General ................................................................................................................................18
13.2 Cleaning...............................................................................................................................18
13.3 Determine the Problem .......................................................................................................18
13.4 Check the Load cell.............................................................................................................18

MWB-SH-e-1810.docx 3
13.5 Load Cell Connections........................................................................................................19
13.6 Check PCB Voltages ...........................................................................................................20
13.7 PCB Input Voltage...............................................................................................................20
13.8 Check Battery Voltage.........................................................................................................20
13.9 Replace Main Board............................................................................................................21
13.10 Replace Battery ...............................................................................................................21
14 Drawing.......................................................................................................... 22
15 Schematic...................................................................................................... 23

4 MWB-SH-e-1810.docx
1 Basic Information
The device must be repaired only by trained specialist staff or personnel with professional
formation (such as a repair-specialist accredited by law concerning verification). The service
manual is obligatory for repair work. After repair, original conditions of the device have to be
restored. Only original spare parts should be used.
Instructions about conformity-evaluated scales:
Repair must be carried only at 100% compliance with the type approval. A violation of this
specification will result in a loss of the type approval! After successful repair the balance will
have to be reverified before it can be used again in a statutorily regulated field.
Detailed instructions about conformity-evaluated scales:
Repair must be carried only at 100% compliance with the type approval. A violation of this
specification will result in a loss of the type approval!
After successful repair the balance will have to be reverified before it can be used again in a
statutorily regulated field.
2 Introdution
This service manual covers the MWB series and is edited for the authorized servicing
personnel.
Note all rights are reserved. Copying any part of this manual is prohibited without our
permission.
In this lineup it is an eco product, Therefore, it is not intended to represent the repair manual
in detail, since the construction of the balance is very simple. It is therefore only referring to
the list of related to disposal spare parts.

MWB-SH-e-1810.docx 5
3 Appliance overview
1. Cover of weighing cell feet
2. Weighing surface
3. Bubble level
4. Hand grip
5. Connection cable
6. Display Unit
Bubble level and handle (2x)
Conveyor roller (2x)

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3.1 Details
Display unit rear side
1
Battery compartment
2
Connecting cable
display unit - platform

MWB-SH-e-1810.docx 7
3.2 Overview display
Display
Designation
Description
GROSS
Gross weight display
Lights up during indication of the gross
weight
NET
Net weight display
Lights up during indication of the net weight
Illuminated after weighing scale was tared
ZERO
Zeroing display
Should the balance not display exactly zero
despite empty scale pan, press the button.
Your balance will be set to zero after a short
standby time.
STABLE
Stability display
Scales are in a steady state
BMI
Body Mass Index
Is actively displayed during active BMI
function
HOLD
HOLD function
Is displayed with active hold function
Battery symbol
Lights when the voltage drops below the
prescribed minimum.
Lights when the battery capacity is almost
exhausted.
Lights when the battery is fully charged.

8 MWB-SH-e-1810.docx
3.3 Overview Keyboard
Button
Designation
Function
ON/OFF button
Turn on/off
HOLD button
Hold function
BMI key
Calculation of the Body Mass Index
In menu:
Confirm selection
For numeric entry:
Confirm numerical value
Function key
In menu:
Call up menu
Select menu items
For numeric entry:
Increase numerical value
Zero setting key
Weighing scale will be reset to „0.0“
For numeric entry:
Change decimal place
TARE key
Tare balance

MWB-SH-e-1810.docx 9
4 Basic Information (General)
4.1 Proper use
This weighing scale is designed for determining the weight of a person whilst standing or
sitting.
On multifunctional weighing scales, the weighed person should carefully step onto the center
of the weighing platform and remain standing without moving. If weighed with a wheelchair,
the wheelchair should remain in the center of the weighing plate.
As soon as a stable weighing value is reached the weighing value can be read.
The weighing scale is designed for continuous duty.
4.2 Improper Use
Do not use these scales for dynamic weighing processes.
Do not leave permanent load on the weighing plate. This may damage the measuring
system.
Impacts and overloading exceeding the stated maximum load (max) of the weighing plate,
minus a possibly existing tare load, must be strictly avoided. This could cause damage to the
balance.
Never operate balance in explosive environment. The serial version is not explosion
protected. It should be noted that a flammable mixture of anesthetics and oxygen or laughing
gas may occur.
The structure of the balance may not be modified. This may lead to incorrect weighing
results, safety-related faults and destruction of the balance.
The balance may only be used according to the described conditions. Other areas of use
must be released by KERN in writing.
The balance cannot be used to determine a body weight in practice of medicine.
4.3 Warranty
Warranty claims shall be voided in case
Our conditions in the operation manual are ignored
The appliance is used outside the described uses
Modification or opening of appliances
Mechanical damage and damage caused by media, liquids,
Natural wear and tear
The appliance is improperly set up or incorrectly electrically connected
The measuring system is overloaded
Dropping of scales
4.4 Monitoring of Test Resources
In the framework of quality assurance the measuring-related weighing properties of the
balances and, if applicable, the testing weight, must be checked regularly. The responsible
user must define a suitable interval as well as type and scope of this test. Information is
available on KERN’s home page (www.kern-sohn.com) with regard to the monitoring of
balance test substances and the test weights required for this. In KERN’s accredited DKD
calibration laboratory test weights and balances may be calibrated (return to the national
standard) fast and at moderate cost.

10 MWB-SH-e-1810.docx
5 Basic Safety Precautions
5.1 Pay attention to the instructions in the Operation Manual
Carefully read this operation manual before setup
and commissioning, even if you are already familiar
with KERN balances.
6 Transport and storage
6.1 Testing upon acceptance
When receiving the appliance, please check packaging immediately, and the appliance itself
when unpacking for possible visible damage.
6.2 Packaging / return transport
Keep all parts of the original packaging for a possibly required return.
Only use original packaging for returning.
Prior to dispatch disconnect all cables and remove loose/mobile parts.
Reattach possibly supplied transport securing devices.
Secure all parts against shifting and damage.